Feeling an attraction to an 18-year-old stranger in an MRT train, a man decided to follow the teenager after fantasising about performing sexual acts on her.
Cheah Chan Yung, who worked in sales at a sports store, followed the girl for about 50 minutes until she almost got to her flat in Paya Lebar and then molested her.
The 24-year-old Malaysian was yesterday sentenced to 14 months' jail and one stroke of the cane.
He pleaded guilty to one count each of molestation and assault.
Deputy Public Prosecutor Rebecca Wong said Cheah spotted the girl after he boarded a west-bound train at Pasir Ris station at around 10pm on July 21 last year.
The DPP said: "The accused observed that she dressed well and found her cute. He felt attracted to her and fantasied about kissing and hugging the victim.
"Throughout the train journey, the accused kept stealing glances at the victim and wanted to 'do sexual things' to the victim."
Cheah followed the girl when she alighted at Paya Lebar station and got on another train.
When she alighted at MacPherson station, he took out a black trash bag from his bag.
The court heard that he had planned to use the trash bag to cover the teenager's face when he molested her. He continued to follow her when she boarded a bus and got off near her home a few stops later.
When the teenager entered a lift at the void deck, he rushed in just as the doors were closing.
As she walked towards her flat on the seventh storey, he suddenly came forward, gripped her upper arms and molested her.
DPP Wong said the teenager tried to resist by hitting Cheah in the chest and shoulder, and called out to her grandmother as she moved towards her flat.
"The accused pulled the victim backwards and covered her mouth from behind with his left hand. This caused the victim to fall to the ground.
"In order to prevent the victim from alerting others, the accused stuffed his fingers into the victim's mouth while kneeling over her."
The girl fought back by biting Cheah's fingers, drawing blood.
He pinned her down by pushing her shoulder and thigh to prevent her from getting up. She screamed and bit his fingers again, causing him to withdraw his hand.
Her younger sister then rushed out of their flat and yelled at Cheah, who stopped the assault.
The police were notified and the victim was taken to KK Women's and Children's Hospital, where she was treated for injuries including bruises on her left limbs.